Dialkyltin,1,4-endoalkylene-2,3-dihydrophthalates and -1,2,3,6 - tetrahydrophthalates



United States Patent 3,479,380 DIALKYLTIN, 1,4-ENDOALKYLENE-2,3-DIHYDRO- PHTHALATES AND -1,2,3,6 TETRAHYDRO- PHTHALATES Pasquale P. Minieri, Woodside, N.Y., assignor to Tenneco Chemicals, Inc, a corporation of Delaware No Drawing. Filed Mar. 3, 1967, Ser. No. 620,251 Int. Cl. C07d 103/00; C07f 7/22; A01n 9/24 U.S. Cl. 260429.7 Claims ABSTRACT OF THE DISCLOSURE Organotin compounds, which have the structural formula wherein each R represents phenyl or an alkyl group having from 4 to 8 carbon atoms; X represents an alkyl group having from 1 to 4 carbon atoms, an alkenyl group having from 4 to 8 carbon atoms, halogen, or phenyl; Z represents methylene, ethylene, chloromethylene, chloroethylene, or oxy; y represents an integer in the range of 0 to 1, and n represents an integer in the range of 0 to 4, effectively control the growth of fungi, and particularly plant pathogens, without causing appreciable'injury to the host plant. Illustrative of these fungicides are di-n-butyl tin 1,4,5,6,7,7-hexachloro-1,4-endomethylene-2,3-dihydrophthalate and di-n-butyl tin 3,4-dimethyl- 6-isobutenyl-1,2,3,6-tetrahydrophthalate.

This invention relates to fungicidal compositions and to a method of controlling the growth of fungi. More particularly, it relates to fungicidal compositions that are suitable for use on living plant materials intended for human or animal consumption and to a method of controlling the growth of fungi on the plant materials through the use of these compositions.

In accordance with this invention, it has been found that certain organotin hydrophthalates are highly effective against a wide variety of plant pathogens, including those responsible for early blight and late blight of tomatoes, powdery mildew of beans, and other serious crop diseases.

The organotin hydrophthalates can be used as the primary fungicidally-active component of the compositions of this invention may be represented by the structural formulas and Xn zero to 4. Illustrative of these compounds are the following:

di-n-butyl tin 1,2,3,6-tetrahydrophthalate,

dioctyl tin 1,2,3,6-tetrahydrophthalate,

di-n-butyl tin 3,4-dimethyl-l,2,3,6-tetrahydrophthalate,

di-n-butyl tin 3,4,5-trimethyl-l,2,3,6-tetrahydrophthalate,

di-n-butyl tin 3,4,6-trimethyl-1,2,3,6-tetrahydrophthalate,

dioctyl tin 3,4-dimethyl-6-isobutenyl-1,2,3,6-tetrahydrophthalate,

diphenyl tin 3,4-dimethyl-6-butyl-1,2,3,6-tetrahydrophthalate,

di-n-butyl tin 1,4-endomethylene-2,3-dihydrophthalate,

diphenyl tin 1,4-endomethylene-2,3-dihydrophthalate,

di-n-butyl tin 1,4,5,6,7,7-hexachloro-1,4-endomethylene- 2,3-dihydrophthalate,

dihexyl tin 1,4,5,6,7,7-hexachloro-1,4-endomethylene- 2,3-dihydrophthalate,

di-n-butyl tin 3rnethyl-6-isopropyl-3,6-endoethylene-2,3-

dihydrophthalate,

dihexyl tin 3,6endoxo-1,2,3,6-tetrahydrophthalate,

diphenyl tin 3,6-dimethyl-3,6-endoxo-l,2,3,6-tetrahydrophthalate,

and the like. A single organotin hydrophthalate or a mixture of two or more of these compounds may be present in the fungicidal compositions of this invention.

The novel fungicidal compounds may be prepared by any suitable and convenient procedure. For example, they may be prepared by the reaction of the appropriate hydrophthalic anhydride with a dialkyl or diaryl tin oxide, or hydrophthalic acid salt with a dialkyl or diaryl tin dichloride. Suitable hydrophthalic anhydrides may be obtained, for example, by the condensation of maleic anhydride with a diene, such as 1,3- hexadiene, 2,4-hexadiene, 3-methyl-2,4-hexadiene, 2,4-dimethyl-l,3-pentadiene, dimethylbutadienes, isoprene, 1,1,3-trimethylbutadiene, 1,1,4-trimethylbutadiene, 1-phenyl-4-methyldiene, alloocimene, 5-methyl-4-isopropyl-1,3-hexadiene, and the like. The compounds in which y in the aforementioned structural formula represents one, that is, those having an endoalkylene or endoxy group, may be prepared by the reaction of a cyclic diene, such as cyclopentadiene or hexachlorocyclopentadiene, with a dialkyl (or diaryl) tin maleate.

While the fungicidal compounds of this invention may be applied as such to the soil, they are ordinarily and preferably combined with an inert fungicidal adjuvant carrier and applied as a solution, emulsion, suspension, or dust. Aqueous solutions or suspension that contain about 0.001 percent to 1 percent by weight and preferably 0.01 percent to 0.5 percent by weight, of the active agent are particularly suitable for this use. These compositions may also contain about 0.01 percent to 0.1 percent by weight of a wetting agent, such as an alkyl sulfate, and alkyl aryl sulfonate, a sulfosuccinate, a polyethylene glycol ether, and the like. Alternatively, the fungicidal compounds may be dissolved in an organic solvent, such as acetone, naphtha, ethylene chloride, or kerosene, and applied as solutions, or they may be mixed with or deposited upon such finely-divided solid carriers as clay, chalk, bentonite, talc, kaolin, fullers earth, and the like and applied as dusts.

The fungicidal compounds may be applied by known techniques to plants, to plant seeds, or to the soil in which plants are growing or are to be grown. They may be applied to the parts of the plants above or in the soil, or the plant seeds may be contacted with the fungicidal compound. Alternatively, the fungicide may be introduced into the soil near the roots of the plants or applied to the surface of the soil and then mixed into the soil to the desired depth.

The amount of the fungicidal composition that is applied is dependent upon such factors as the species of plant being treated and the plant pathogen whose control is desired and is that amount which will inhibit or prevent the growth of the plant pathogen while causing little or no injury to the plants. About 1 pound to 200 pounds of the active compound is ordinarily applied per acre, with particularly good results being obtained when pounds to 35 pounds per acre is used.

The substituted tin hydrophthalates may be used as the sole active component of the fungicidal compositions. If desired, however, these compositions may also contain other fungicides, such as sulfur and the metal dimethyldithiocarbamates; insecticides, such as DDT and benzene hexachloride; or plant nutrients, such as urea, ammonium nitrate, and potash.

The invention is further illustrated by the examples that follow.

EXAMPLE 1 A. To 476 grams (3.5 moles) of freshly-distilled alloocimene was added a solution of 245 grams (2.5 moles) of maleic anhydride in 720 grams (8.17 moles) of ethyl acetate at such a rate that the temperature rose to 88- 90 C. and remained at that temperature throughout the addition. The reaction mixture was heated with stirring at 8890 C. for 5 hours and then heated under vacuum to remove the ethyl acetate. The residue was distilled under reduced pressure to remove unreacted allo-ocimene from the product. There was obtained about 450 grams of 3,4-dimethyl-6 isobutenyltetrahydrophthalic anhydride.

B. A mixture of 24.9 grams (0.1 mole) of di-n-butyl tin oxide and 150 ml. of toluene was heated to its reflux temperature to remove traces of water by azeotropic distillation and then cooled. 3,4-dimethyl-6-isobutenyltetrahydrophthalic anhydride (23.4 grams, 0.1 mole) was added, and the reaction mixture was heated at its reflux temperature for 3 hours and then allowed to stand at room temperature overnight. Upon removal of the toluene by distillation under vacuum, there was obtained 48.3 grams of di-n-butyl tin, 3,4-dimethyl-6-is0butenyl-1,2,3,6- tetrahydrophthalate, which contained 24.3 percent Sn (calculated for C H O Sn, 24.6 percent Sn).

EXAMPLE 2 A mixture of 24.9 grams (0.1 mole) of di-n-butyl tin oxide in 160 ml. of toluene was heated to its reflux temperature to remove traces of water by azeotropic distillation and then cooled. Tetrahydrophthalic anhydride (15.2 grams, 0.1 mole) was added, and the reaction mixture was heated at its reflux temperature for 3 hours and then allowed to stand at room temperature overnight. Upon removal of the toluene by distillation under vacuum, there was obtained 40.2 grams of di-n-butyl tin 1,2,3,6-tetrahydrophthalate, which melted at 72 74.5 C. and which contained 30.2 percent Sn (calculated for C H O Sn, 29.0 percent Sn).

EXAMPLE 3 A mixture of 9.9 grams (0.15 mole) of cyclopentadiene, 49.4 grams (0.15 mole) of dibutyl tin maleate, and 200 ml. of benzene was stirred at room temperature for 4.5 hours and then heated at its reflux temperature for 2 hours. After being cooled slowly to room temperature, the reaction mixture was heated under vacuum to remove the benzene. The residue was recrystallized from dilute acetic acid. There was obtained 45.2 grams of di-n-butyl tin 1,4-endomethylene-2,3-dihydrophthalate, which melted at 222227 C. and which contained 29.6 percent Sn (calculated for C H O Sn, 28.7 percent Sn).

EXAMPLE 4 A mixture of 109.2 grams (0.4 mole) of hexachlorocyclopentadiene, 32.9 grams (0.1 mole) of di-n-butyl tin maleate, and 200 ml. of xylene was heated at its reflux temperature for 18 hours. After being cooled slowly to room temperature, the reaction mixture was heated under vacuum to remove the xylene. The residue was recrystallized from methanol and dried under vacuum at 60 C. There was obtained 47.2 grams of di-n-butyl tin 1,4,5,6,7, 7-hexachloro-1,4-endomethylene 2,3 dihydrophthalate, which melted at 160170 C.

EXAMPLE 5 A mixture of 150 ml. of toluene and 24.9 grams (0.1 mole) of di-n-butyl tin oxide was heated to its reflux temperature to remove traces of water by azeotropic distillation and then cooled. To this mixture was added 10 ml. of toluene and 37.1 grams (0.1 mole) of 1,4,5,6,7,7- hexachloro 1,4 endomethylene 2,3 dihydrophthalic anhydride (chlorendic anhydride). The reaction mixture was heated at its reflux temperature for 3.25 hours, cooled, and then heated to distill off the toluene. After being dried overnight at 60 C./1 mm., there was ob tained 62 grams of di-n-butyl tin 1,4,5,6,7,7,-hexachloro- 1,4-endomethylene-2,3-dihydrophthalate, which contained 33.4 percent Cl and 19.1 percent Sn (calculated for C H Cl O Sn, 34.6 percent Cl and 19.4 percent Sn).

EXAMPLE 6 Acetone solutions were prepared by dissolving 100 mg. portions of the products of Examples 15 in 10 ml. of acetone that contained 2000 p.p.m. of sorbitan trioleate (Span and 5000 p.p.m. of a polyoxyethylene ether of sorbitan monooleate (Tween 80). The acetone solutions were dispersed in ml. portions of distilled water to form aqueous solutions that contained 1000 p.p.m. of the fungicidal compound. More dilute solutions were prepared by adding distilled water to these solutions.

EXAMPLE 7 A series of experiments was carried out in which tomato plants which had been sprayed with the aqueous solutions of Example 6 were sprayed with a suspension of spores of Alternarz'a solani, the fungus that causes early blight of tomatoes. One week after treatment, the degree of suppression of the disease was noted. The results are given in Table I.

Tender green bean plants with fully expanded primary leaves were inoculated with spores of Erysiphe po lygoni, the powdery mildew fungus. Forty-eight hours later, the plants were sprayed with aqueous solutions prepared by the process of Example 6. After a period of 7-10 days, the degree of suppression of the disease was noted. The results obtained are summarized in Table II.

TABLE II Concentration of funglcide in Control of aqueous solution powdery mildew Funglcide (p.p.m.) of beans Product of Ex. 1 1, 000 Good control. Product of Ex. 2 1,000 Do. Product of Ex. 4 1,000 Complete control.

500 Fair control.

The terms and expressions which have been employed are used as terms of description and not of limitation.

There is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed.

What is claimed is:

1. An organotin compound selected from the group con sisting of compounds having the structural formula I? /c-o R 4 Xn z sn and compounds having the structural formula Xn n wherein each R represents a member selected from the group consisting of phenyl and alkyl groups having from 4 to 8 carbon atoms; X represents a member selected from the group consisting of alkyl groups having from 1 to 4 carbon atoms, alkenyl groups having from 4 to 8 carbon atoms, halogen, and phenyl; Z represents a member selected from the group consisting of methylene, ethylene, chloromethylene, and chloroethylene; y represents an integer in the range of zero to 1; and n represents an integer in the range of zero to 4.

2. The compound as set forth in claim 1 that has the structural formula 6 3. The compound as set forth in claim 1 that has the structural formula 4. The compound as set forth in claim 1 that has the structural formula 5. The compound as set forth in claim 1 that has the structural formula References Cited UNITED STATES PATENTS TOBIAS E. LEVOW, Primary Examiner W. F. W. BELLAMY, Assistant Examiner US. Cl. X.R. 

